The West Fork Fire “spotted” over the Continental Divide and established itself in the Rio Grande National Forest. The Windy Pass Fire was within 400 feet of the Wolf Creek Ski Area boundary.

Evacuations were in place from the top of Wolf Creek Pass down to the outer limits of South Fork, a tiny town on the east side of the pass with a population of 386, according to the 2010 census.

Durango-area residents caught sight of another wildfire Thursday evening – the Papoosa Fire north of Creede, more than 60 miles to the northeast. It was burning in the Weminuche Wilderness near Rio Grande Reservoir.

An 18-mile stretch of U.S. Highway 160 over Wolf Creek Pass closed about 2:30 p.m. Thursday. It will remain closed indefinitely. Fire officials said smoke was causing poor visibility, and the fire could make it to the highway late Thursday or early this morning.

The West Fork Fire, burning primarily in the Weminuche Wilderness, more than tripled in size Wednesday, from 3,879 acres to 12,001 acres. It was estimated at 17,000 acres Thursday night.

Meanwhile, the nearby Windy Pass Fire went from 191 acres to 709 acres Wednesday. It was estimated at 1,000 acres Thursday night, It came within 400 feet of the boundary at Wolf Creek Ski Area.

Federal firefighters planned to provide structure protection at the ski area, including for terminals at the top of lifts and for at least a dozen structures at the base area.

“This place is fairly defensible; there's a lot of open space around here,” said Steve Till, a fire information officer. “All this open space makes a safety zone. If they had to pull out, they would be OK. It'd be kind of smoky, but it'd be safe.”

Both fires were tearing through a sea of dead, standing trees, victims of the spruce bark beetle infestation.

Davy Pitcher, owner of the ski area, stood calmly Thursday at the base of the ski area wearing boots, tan jeans, a plaid shirt and a ball cap. Smoke from the Windy Peak Fire crept over a ridgeline from the south, while a massive plume from the West Fork Fire billowed to the north, across the highway.

Pitcher seemed almost at peace with the situation. He described wildfire as a natural process – the light at the end of the tunnel of what has been a slow death of millions of spruce trees that blanket both sides of Wolf Creek Pass.

“While it's a little disconcerting to see big fires, in the long run, it's probably good for the forest's health,” he said. “The spruce beetle was a slow death.”

The beetles began to invade about 13 years ago. He spent about $100,000 annually trying to remove dead trees, but he abandoned the tactic three years ago after the forest became overrun.

The forest will never be the same in our lifetimes, he said, but the undeveloped ski area will continue to receive some of deepest snowfalls in Colorado.

“It might be somewhat different to look at, but it's still a beautiful place,” he said.

If the fire reached the ski area, he planned to fire up the diesel chairlifts and water down the cables. If the cables get too hot in any one location, they will unwind and fail, sending all the chairs crashing to the ground, he said.

“We hope to be able to protect the chairlifts,” Pitcher said. “They're a little harder to protect.”

Firefighters were prepared to protect all structures at the ski area, said Dirk Rogers, task force leader with the U.S. Forest Service. They had pumps connected to streams and trucked in water from 30 minutes away.

The biggest threat was hot embers falling on cedar shake-shingle rooftops, he said.

“It doesn't take but one ember to get shoved up under one of those shingles to cause a problem,” Rogers said.

The National Incident Management Organization took over command of the fire Thursday.

A public meeting was held Thursday night in South Fork, which has been heavily impacted by smoke during the last few days. More than 800 people attended, and fire officials had to break it into two sessions to accommodate everybody.

South Fork itself is not under evacuation.

Shelter locations were set up at Del Norte High School for people, and at the Sky High Complex in Monte Vista for RVs and large animals.

The Colorado Department of Transportation has given no estimate for when Wolf Creek Pass may reopen.

Dolph and Sabina Kuss of Durango were on their way to a bicycle race in Leadville when they got stopped at the base of Wolf Creek Pass. A Colorado State Patrol trooper told them the smoke was so thick it was difficult to see.

“He said it was like a whiteout in a snowstorm,” Dolph Kuss said while eating cheese slices.

They had been waiting for about 20 minutes with no idea whether the pass would reopen anytime soon.

“We have a Spanish book, a bag of chips and some lemonade, so when that gets old, we'll go (back to Durango),” Sabina Kuss said. “Neither of us likes to drive, so this is an excuse to pull over. It's kind of early in the trip, though.”